The utilization of simultaneous-equations systems in econometric models of national economies has a long and useful tradition among economists and policymakers. Only recently, however, has the simultaneous-equations approach been applied in the context of a model of population redistribution in the United States. Although this approach lends itself to a rigorous policy orientation, such an orientation has not yet been adopted in connection with a model of migration and urban-regional growth. While the application of the simultaneous-equations approach to regional development planning may be very useful to policy makers in advanced economies, such an application has particular relevance to less-developed economies that are experiencing rapid population growth, uneven regional growth and maldistribution of income. We propose to apply such a model to Mexico. The results of the research will not only be useful to the Mexican authorities but also to those of other less-developed countries. Since migration is both a cause and consequence of economic, social and demographic conditions in sending (rural) areas and receiving (urban) areas, we propose to specify and to estimate by means of appropriate econometric techniques (two and three stage least squares) a simultaneous-equations model of migration and urban-regional growth in Mexico. The model will account for the interaction between the causes and effects of migration and examine the (employment, unemployment, income, and migration) linkages between urban areas and their agricultural hinterlands. Governments have had no conscious integrated policies for national programs of population distribution, and little is known of the specific mechanisms by which governments could influence population distribution. Our proposed research would explicitly include policy variables that would allow us to derive multipliers showing the effects of government policies (including family planning) upon urban migration and regional growth in Mexico.